/*******************************************************************************
 * Copyright (c) 2000, 2005 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package com.architexa.org.eclipse.draw2d;

import com.architexa.org.eclipse.draw2d.geometry.Point;

/**
 * An object to which a {@link Connection} will be anchored.  If the ConnectionAnchor
 * moves, the Connection should move with it.
 */
public interface ConnectionAnchor {
	
/**
 * Adds a listener interested in the movement of this ConnectionAnchor.
 * @param listener The AnchorListener to be added
 */
void addAnchorListener(AnchorListener listener);

/**
 * Returns the location where the Connection should be anchored in absolute coordinates. 
 * The anchor may use the given reference Point to calculate this location.
 * @param reference The reference Point in absolute coordinates
 * @return The anchor's location
 */
Point getLocation(Point reference);

/**
 * Returns the IFigure that contains this ConnectionAnchor.  Moving this figure will cause
 * the anchor to move with it.
 * @return The IFigure that contains this ConnectionAnchor
 */
IFigure getOwner();

/**
 * Returns the reference point for this anchor in absolute coordinates. This might be used
 * by another anchor to determine its own location (i.e. {@link ChopboxAnchor}).
 * @return The reference Point
 */
Point getReferencePoint();

/**
 * Removes the listener.
 * @param listener The AnchorListener to be removed
 */
void removeAnchorListener(AnchorListener listener);

}
